An oak is a hardwood tree or shrub in the genus Quercus of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne in a cup. The genus is widely distributed in the Northern Hemisphere; it includes some 500 species, both deciduous and evergreen. Fossil oaks date back to the Middle Eocene. Molecular phylogeny shows that the genus is divided into Old World and New World clades, but many oak species hybridise freely, making the genus's history difficult to resolve.
Quercus marilandica, the blackjack oak, is a small oak, one of the red oak group Quercus sect. Lobatae. It is native to the eastern and central United States.
Quercus robur, the pedunculate oak, is a species of flowering plant in the beech and oak family, Fagaceae. It is a large tree, native to most of Europe and western Asia, and is widely cultivated in other temperate regions. It grows on soils of near neutral acidity in the lowlands and is notable for its value to natural ecosystems, supporting a very wide diversity of herbivorous insects and other pests, predators and pathogens.
Quercus garryana is an oak tree species of the Pacific Northwest, with a range stretching from southern California to southwestern British Columbia. It is commonly known as the Garry Oak, Oregon white oak or Oregon oak. It grows from sea level to an altitude of 690 feet in the northern part of its range, and from 980 to 5,900 ft in the south of the range in California. The eponymous Nicholas Garry was deputy governor of the Hudson's Bay Company.
Quercus suber, commonly called the cork oak, is a medium-sized, evergreen oak tree in the section Quercus sect. Cerris. It is the primary source of cork for wine bottle stoppers and other uses, such as cork flooring and as the cores of cricket balls. It is native to southwest Europe and northwest Africa. In the Mediterranean basin the tree is an ancient species with fossil remnants dating back to the Tertiary period.
Quercus virginiana, also known as the southern live oak, is an evergreen oak tree endemic to the Southeastern United States. Though many other species are loosely called live oak, the southern live oak is particularly iconic of the Old South. Many very large and old specimens of live oak can be found today in the Deep South region of the United States.
Quercus agrifolia, the California live oak, or coast live oak, is a highly variable, often evergreen oak tree, a type of live oak, native to the California Floristic Province. It may be shrubby, depending on age and growing location, but is generally a medium-sized tree. It grows west of the Sierra Nevada mountain range from Mendocino County, California, south to northern Baja California in Mexico. It is classified in the red oak section of oaks.
Quercus douglasii, known as blue oak, is a species of oak endemic to California, common in the Coast Ranges and the foothills of the Sierra Nevada. It is California's most drought-tolerant deciduous oak, and is a dominant species in the blue oak woodland ecosystem. It is occasionally known as mountain oak and iron oak.
An oak savanna is a type of savanna—or lightly forested grassland—where oaks are the dominant trees. The terms "oakery" or "woodlands" are also used commonly, though the former is more prevalent when referencing the Mediterranean area. These savannas were maintained historically through wildfires set by lightning, humans, grazing, low precipitation, and/or poor soil.
Quercus falcata, also called southern red oak, spanish oak, bottomland red oak or three-lobed red oak is an oak. Native to the southeastern United States, it gets its name the "Spanish Oak" as these are the areas of early Spanish colonies, whilst "southern red oak" comes from both its range and leaf color during late summer and fall. The southern red oak is a deciduous angiosperm, so has leaves that die after each growing period and come back in the next period of growth.
Quercus coccifera, the kermes oak, is an oak bush in the Ilex section of the genus. It has many synonyms, including Quercus calliprinos. It is native to the Mediterranean region and Northern African Maghreb, south to north from Morocco to France and west to east from Portugal to Cyprus and Turkey, crossing Spain, Italy, Libya, Balkans, and Greece, including Crete. The Kermes Oak was historically important as the food plant of Kermes scale insects, from which a red dye called crimson was obtained. The etymology of the specific name coccifera is related to the production of red cochineal (crimson) dye and derived from Latin coccum which was from Greek κόκκος, the kermes insect. The Latin -fera means 'bearer'.
Quercus phellos, the willow oak, is a North American species of a deciduous tree in the red oak group of oaks. It is native to the south-central and eastern United States.
Quercus lyrata, the overcup oak, is an oak in the white oak group. The common name, overcup oak, refers to its acorns that are mostly enclosed within the acorn cup. It is native to lowland wetlands in the eastern and south-central United States, in all the coastal states from New Jersey to Texas, inland as far as Oklahoma, Missouri, and Illinois. There are historical reports of it growing in Iowa, but the species appears to have been extirpated there. It is a slow-growing tree that often takes 25 to 30 years to mature. It has an estimated lifespan of 400 years.
Quercus canariensis, the Algerian oak, Mirbeck's oak or zean oak, is an oak native to southern Portugal, Spain, Tunisia, Algeria and Morocco. Despite the scientific name, it does not occur naturally today in the Canary Islands, though it may have in the past. It is placed in section Quercus.
Quercus chrysolepis, commonly termed canyon live oak, canyon oak, golden cup oak or maul oak, is a North American species of evergreen oak that is found in Mexico and in the western United States, notably in the California Coast Ranges. This tree is often found near creeks and drainage swales growing in moist cool microhabitats. Its leaves are a glossy dark green on the upper surface with prominent spines; a further identification arises from the leaves of canyon live oak being geometrically flat.
Quercus acerifolia is a rare North American species of oak in the red oak section of Quercus. It is endemic to just four locations within the Ouachita Mountains of the State of Arkansas.
Quercus alnifolia, commonly known as the golden oak, is an evergreen oak species of Cyprus. Its common English name refers to the golden coloured lower surface of its leaves. Quercus alnifolia belongs to the endemic flora of the island and it is confined to the igneous geological complex of the Troodos Mountains. In February 2006, the parliament of Cyprus selected the golden oak to be the country's national tree.
The Tyrrhenian-Adriatic sclerophyllous and mixed forests is an ecoregion in southern Italy, Sicily, Sardinia, Corsica, the Dalmatian Islands of Croatia, and Malta.
Quercus pyrenaica, also known as Pyrenean oak, or Spanish oak is a tree native to southwestern Europe and northwestern North Africa. Despite its common name, it is rarely found in the Pyrenees Mountains and is more abundant in northern Portugal and north and northwestern Spain.
Quercus myrtifolia, the myrtle oak, is a North American species of oak. It is native to the southeastern United States. It is often found in coastal areas on sandy soils.
